1. Field of the Invention
The present invention relates generally to devices and methods for locating catheters in vivo, and more particularly to devices and methods that provide a visible indication of the in vivo location and orientation of a catheter distal end section.
2. Description of the Prior Art
It is often difficult to determine the location and orientation of a catheter distal end portion and to determine the direction to steer it to get to a desired location. This can be particularly problematic when steering a bi-directional catheter which has become twisted and convoluted within the patient's anatomy, whereupon it is difficult to tell which direction to manipulate the catheter handle relative to the steerable distal end portion of the catheter. At times, the catheter movement can be critical, especially if catheter placement has been difficult and the physician needs to adjust the placement a minor amount. In this situation, he needs to know which direction to properly steer the catheter end portion.
To accomplish catheter steering, a fluoroscope is typically utilized to provide real time in vivo viewing of the catheter end portion location and orientation. However, the fluoroscopic view is generally two dimensional, and owing to various twists that a guide tube and end portion may have, the in vivo fluoroscopic viewing of the catheter end portion leaves much to be desired.
The present invention includes marker elements within the catheter end portion that are more fluoroscopically visible than the currently utilized end portion materials. The efficacious positioning of such markers, as disclosed herebelow, provides enhanced fluoroscopically visible information to the physician regarding the location and orientation of the catheter end portion, thus enabling the physician to determine which direction to manipulate a steering mechanism to adjust the catheter end portion location and orientation.